24hrs to get wet.
You should seal the grout. Especially if its light colored grout. It helps prevent staining of the grout from dirt, oils, shampoos, soaps, etc. Tell your husband they have sealer in an aresol can called Stand and Seal. Took me 1 minute to seal my bath floor. Just stand and spray. I put on 2 coats.
Just have plenty of ventilation when using it.
